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GT350 OEM ECU Software Update - Piston Slap Reduction

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Some of you might know that I have a genuine Ford VCM II OBD connector, the one the dealerships use. Once or twice a year, I get a short-term Motorcraft IDS software license so I can hook up to the car and do the diff oil service and otherwise check to see that the electronics are all happy. This time, when I got the system all loaded up and connected, I also updated the ECU software to the latest version. I didn't expect much difference; I was curious, more than anything.

Well, I have to say "It's different". Really different. Piston slap on my engine has always been annoying and loud. It's pretty much gone now - it's there if you listen for it, but it's not as obtrusive as it used to be by a long ways. The engine runs smoother too. Nothing major, but the flat spots in the torque curve are gone. It's a different feel from what it was. There seems to be a bit more torque lower down, but it could be an illusion. Anyway, I like it.

So, for those of you who want to reduce piston slap, Ford has released a new software version for at least the 2016's that reduces it. Getting it installed is another matter. Unless you invest in a lot of expensive tools, it's not a DIY job. Independent shops can do it, and of course a dealer can, although the cost of installation won't be covered by warranty. And before anyone asks, it's way beyond anything that Forscan can do.
 
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This sounds significant, no? Even though you can't use warranty as justification for the dealer doing the update, if they are willing to, that shouldn't affect the engine warranty, correct?
 
Very interesting. I wonder if there will be a service bulletin on this.
 
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Very interesting. I wonder if there will be a service bulletin on this.
There is a service bulletin for piston slap, but it says "don't worry about it - it's normal - take no action". What alerted me to the availability of a new PCM software release was a different service bulletin that had nothing to do with piston slap, but where the solution was to install the PCM code update. I was curious, and once you have the tools and the licenses, it's free, so I installed it.

The second service bulletin was about stuck muffler (exhaust sound) valves caused by ice and cold weather. Apparently the new software doesn't block drive mode changes when the valves are stuck. Whether that leaves the door open to owners blocking them open or closed all the time, I have no idea - the bulletin doesn't say - but it's a possibility.

As to warranty coverage, it's genuine Ford software from Ford directly and there is at least one service bulletin that says "install it", so it won't affect warranty.
 
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Virginia
Wow...I haven't heard anything on mine...I think. I would be curious to know if this is something that will be done when cars are in for service or by request in the future?
 
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The more I drive this version, the more I like it. Low end torque is much better and smoother, more like what you'd expect from a 5.2 liter V8. The changes have definitely altered the piston slap too. It's still around but it's in new places on the power curve - the best part is that it's not happening on the long level stretches of road that used to drive me nuts. I don't know how Ford can move it around like this, but I do recall "piston slap" programming that was in my 2011 Mustang Coyote calibration, so there must be something in the timing that softens it up.
 

captdistraction

GrumpyRacer
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Interesting. My GT350 is pretty noisy down low, and anything that boosts its otherwise dismal low end torque and tip-in response would be awesome.

I just figured that's where the engine had to be, but I'll keep an eye out for a TSB that refers to the update, otherwise no way will I be able to get our local dealer to flash it. I'd try it with my VCM clone, but just too damn risky :)
 
If they went through the process of making the software update and it is better, why not install it on all ECUs? My 6.7L PSD F350 has had several updates in the 4 years I've had it. Most of them were for durability and to prevent excessive limp-mode situations when a sensor goes bad or something like that. The dealer loads them whenever I go, I don't even have to ask.
 
Wow...I haven't heard anything on mine...I think. I would be curious to know if this is something that will be done when cars are in for service or by request in the future?

I asked the service manger at my local dealer. He couldn't give me a definitive answer and stated they have to plug the car into their diagnostics to see whats actually available (?).
If there is any updated software out there, he said he would update the ECU. They were too busy that day so
I hope to find out this week when I go in for a state inspection.
 
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I asked the service manger at my local dealer. He couldn't give me a definitive answer and stated they have to plug the car into their diagnostics to see whats actually available (?).
If there is any updated software out there, he said he would update the ECU. They were too busy that day so
I hope to find out this week when I go in for a state inspection.
That's the way it works - they plug the car into the diagnostic system and it checks the Ford database for software updates. The check is based on the actual version that's already installed, so if you've been updated before to the current level, it won't do it again. Your G# is lower than mine, so it's likely that it rolled out of the factory with the same or perhaps even older software than mine did.

Make sure they do the inspection before the update - updating clears the emission system ready codes and your car will probably flunk.
 
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Here's the Service Bulletin that started all this - I saw the "And Reprogram The PCM" words and went from there:

TSB 18-2290.jpg
 
The more I drive this version, the more I like it. Low end torque is much better and smoother, more like what you'd expect from a 5.2 liter V8. The changes have definitely altered the piston slap too. It's still around but it's in new places on the power curve - the best part is that it's not happening on the long level stretches of road that used to drive me nuts. I don't know how Ford can move it around like this, but I do recall "piston slap" programming that was in my 2011 Mustang Coyote calibration, so there must be something in the timing that softens it up.

Just had my ECU flashed today at the local dealer (after state inspection) and can attest to the above statements. I brought a copy of the TSB @JAJ posted earlier as a reference... just in case.
The tech commented there were no codes but he had heard of the flash offering some improvements so he pushed it through without any debate. Not day & night but definitely a difference. Almost like a mild tune.
Not sure if there's a placebo effect as well but my exhaust seems to crackle & pop just a bit more too.
The best part was $0 charged after I was initially quoted 1 hr of labor when I arrived.
 
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... my exhaust seems to crackle & pop just a bit more too...
Funny you should mention that. A uniformed LEO was directing traffic at a covered outdoor parking area that serviced a secure building. As I was walking to the building, he waved me over and started asking questions about the Shelby. Apparently, a buddy of his had one and he was curious. We chatted for a bit and then I went inside. He was still there when I came back out, so as I was leaving, I fired it up, switched to Sport exhaust and blipped it once. I've never heard it bark like that before, and I've been listening to mine for three years. Then I slipped it into gear and rolled out of his parking lot at a stately 10 MPH.
 

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I gave the dealer a copy of what @JAJ had posted.
It has all the info they needed.
I just made it clear why I really wanted the ECU update.
Nice free upgrade
Thanks! I was on the phone with my local SA earlier today. I basically read the 18-2290 TSB off to him, verbatim. He knew of that TSB and said the easiest thing to do is get the car in and get it hooked up for diagnostics. They will receive prompts if any software updates are available. Once I'm done, I'll update with any new info I've been provided.
 

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